Re: LuaRocks installation (Ubuntu Linux)

[Hisham <h@...>]

On 24 July 2018 at 10:46, Dirk Laurie <dirk.laurie@gmail.com> wrote:
> I have an opportunity to add LuaRocks from scratch on a machine that
> did not yet have even Lua.
>
> I did the following on an Ubuntu 16.04 laptop recently handed down to me:
>
> 1. Downloaded Lua 5.3.5 into a local directory, built it (I needed to
> do that twice, installing libreadline-dev in between), installed it
> (it goes to /usr/local by default).

This is the expected behavior, because Linux applications installed by
hand should install into /usr/local.

> 2. Installed luarocks via the APT tool. This installs luarocks 2.2.0,
> and also lua 5.1,

Which is unfortunately quite out-of-date. Please nag the maintainers
of your favorite distro for updated LuaRocks versions. :)

> in /usr, not /usr/local.

Again, this is expected behavior, because Linux applications installed
via package manager should install into /usr.

> It came as a bit of a shock that a two-year old distro still installs
> 5.1 as default lua.

Please nag the maintainers of your favorite distro for updated Lua versions. :)

> Questions:
>
> 1. How do I get Luarocks to install 5.3 versions?

Install it from source, the same way you installed Lua (as a general
guideline, using the same installation method for your Lua and your
LuaRocks should result in compatible combinations.)

> 2. Can one install Luarocks 3.0.0 via an older Luarocks?

Unfortunately not, because this is a major release with some bigger
architectural changes.

However, future LuaRocks 3.x will be installable from LuaRocks 3.0
(provided you install it as a rock using "make bootstrap" — there is
also a standard "make install" rule which installs it as a regular
non-rock application, which is useful for distro maintainers)

> It came as a bit of a shock that a two-year old distro still installs 5.1 as default lua.

That is indeed unfortunate. The good news is that a single LuaRocks
3.0 installation can manage packages for any Lua/LuaJIT
version/installation (using flags --lua-version and --lua-dir), no
matter what Lua version LuaRocks itself is using to run (this is one
of those big architectural changes!). So in the future such mismatches
will no longer be a hassle.

Hope this helps!

-- Hisham